Although colon cancer is the second leading cause of cancer death in the United States, it is also often treatable. Early detection of colon polyps is a key to treatment. CT colonography (CTC), also known as virtual colonoscopy, is a promising new non-intrusive detection technique where polyps are identified from CT scans, sometimes with the aid of a computer-aided detection (CAD) system.
However, virtual colonoscopy can be plagued by false positives. False positives are troublesome because any identified positives must be considered and evaluated by a human classifier such as a physician or technologist. Even if a feature can be quickly dismissed as a false positive, too many false positives consume an inordinate amount of time and limit the usefulness of the software-based approach.
Thus, more work is needed to increase specificity by filtering out false positives and otherwise improving virtual colonoscopy technologies.